1. Field
Apparatuses, devices, and articles of manufacture consistent with the present disclosure relate to audio encoding and decoding, and more particularly, to a noise filling method for generating a noise signal without additional information from an encoder and filling the noise signal in a spectral hole, an audio decoding method and apparatus, a recording medium and multimedia devices employing the same.
2. Description of the Related Art
When an audio signal is encoded or decoded, it is required to efficiently use a limited number of bits to restore an audio signal having the best sound quality in a range of the limited number of bits. In particular, at a low bit rate, a technique of encoding and decoding an audio signal is required to evenly allocate bits to perceptively important spectral components instead of concentrating the bits to a specific frequency area.
In particular, at a low bit rate, when encoding is performed with bits allocated to each frequency band such as a sub-band, a spectral hole may be generated due to a frequency component, which is not encoded because of an insufficient number of bits, thereby resulting in a decrease in sound quality.